This invention relates to a muffler mechanism used for damping sounds to be generated on a grand piano.
For damped performance on a grand piano, it is conventionally employed to move the keys with the action assemblies sideways in order to reduce the number of strings to be striken by hammers. For example in the case of strings in the treble range, only two out of three strings are striken for damped performance. With this conventional construction, however, a large space has to be reserved for the lateral movement of the keys and the action assemblies. Use of a pedal and a lever mechanism for this purpose connects to a complicated construction and increased parts number.
In order to avoid such drawbacks, Japanese Patent Publication No. Sho.45-22294 proposes a new construction in which, like on an upright piano, a muffler is selectively interposed between an array of strings and an array of hammer in order to damp striking by the hammers. With this earlier proposal, however, the muffler has to be arranged in front of the striking positions on the strings whilst requiring a large space for mounting. Such arrangement seriously interferes with adjustment of the action assemblies. Back and front movement of the horizontally arranged muffler necessitates some extent of rigidity of the muffler which unavoidably lowers the damping effect. Despite such extent of rigidity, the horizontally arranged muffler is vulnerable to deformation. Horizontal movement of the muffler requires a complicated construction of its drive mechanism.